1. Field of the Technology
The technology presented herein relates to a storage medium having a game program stored thereon and a game apparatus, and more specifically to a game apparatus for executing game processing based on a state of an input device, which is at least one of a position and a moving speed of the input device, and a storage medium having a game program for such game processing stored thereon.
2. Description of the Background Art
Conventionally, games playable using an optical pointing device have been proposed. Such games include, for example, a shooting game of shooting a target displayed on a screen using an input device mimicking a gun (hereinafter, referred to as a “gun-type controller”). A gun-type controller used for such a game includes a CCD camera. A light emitting element is provided in the vicinity of the screen as an imaging target, so that the CCD camera takes an image encompassing the light emitting element. Based on the obtained image data, the position of the light emitting element in the taken image is obtained. Based on the position of the light emitting element, the position on the screen pointed to by the gun-type controller is calculated (for example, Japanese Laid-Open Patent Publication No. 8-71252).
A game apparatus using a gun-type controller including a light receiving sensor and an inclination sensor is also disclosed (for example, Japanese Laid-Open Patent Publication No. 2001-104643). With this game apparatus, an amount of light used for raster-scanning the screen is detected by the light receiving sensor, and the position on the screen which is hit by the bullet is detected based on the amount of light. The inclination sensor is structured so as to become conductive when the gun-type controller is inclined at a predetermined angle, utilizing the conductance effect of mercury. Based on whether the inclination sensor is conductive or not, an offense state or a defense state is selectively input.
A game apparatus using an input device including an acceleration sensor is also disclosed (for example, Japanese Laid-Open Patent Publication No. 2002-153673). With this game apparatus, a boxing game is playable. A glove-shaped input device having a built-in three-axial acceleration sensor is put on a hand of a player. When the player performs an operation of making a punch, the acceleration sensor determines the type of the punch (straight, hook, upper, etc.) made by the player.
However, the conventional game apparatuses disclosed in the above-identified publications have the following problems. With the game apparatus described in Japanese Laid-Open Patent Publication No. 8-71252, the gun-type controller is used only to specify a position on the screen. Therefore, the player using the gun-type controller can only perform one type of operation of indicating a position on the screen. Such a game operation is too plain to make the game amusing to play.
With the game apparatus described in Japanese Laid-Open Patent Publication No. 2001-104643, the player can perform an operation only based on whether the inclination sensor is conductive or not, i.e., only an operation of selecting one of two alternatives. Such a game operation, although being slightly more complicated than that provided by Japanese Laid-Open Patent Publication No. 8-71252, is still too plain to make the game amusing to play.
The game apparatus described in Japanese Laid-Open Patent Publication No. 2002-153673 merely determines the type of the punch, i.e., the motion of the player's hand, by the acceleration sensor and reflects the motion on the game image. The game apparatus does not allow the player to specify a position on the screen and reflect the motion of his/her hand detected by the acceleration sensor on an object existing at the specified position.
In addition, the game apparatus described in Japanese Laid-Open Patent Publication No. 2002-153673 does not detect a posture of the input device. Whether the player may make a straight punch forward or upward, the punch is determined merely as a “straight punch”. Even if the player makes a straight punch upward, a straight punch is displayed as being made forward on the screen. Namely, the motion, intended by the player, of making a straight punch upward is not reflected. This may result in a game with very poor operability.